<meta charset="UTF-8">
<style>
    body{
        background:url(https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fpic.vjshi.com%2F2019-05-04%2Fb233cffa4e0cfcbece18697ace00daba%2F00003.jpg%3Fx-oss-process%3Dstyle%2Fwatermark&refer=http%3A%2F%2Fpic.vjshi.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=auto?sec=1652865572&t=6b06c7dfce8fe82183852a9a13c024ee) ;
        background-size: 100%;
    }
    div{
        font-size: 150px;
        position: absolute;
        left: 270px;
        top: 260px;
    }
</style>
<div>🤾🏿‍♂️</div>
<script>
    //1.给网页绑定鼠标移动事件
    document.onmousemove = function(evt){
    //2.事件处理函数中  - 最终获取当前鼠标位置  相对于网页左上角
    var e = evt || window.event
    var left = e.pageX
    var top = e.pageY
    //3.事件处理函数中  - 设置鼠标移动位置
    var divObj = document.querySelector('div')
    divObj.style.left = left -divObj.clientWidth/2 + 'px'
    divObj.style.top = top  -divObj.clientHeight/2 + 'px'
}
</script>